YAHF: The Other Side of the Coin. Xander Harris finds himself inside Lex Luthor's body in the DC Universe. He's sure his friends will eventually rescue him, so he decides to toss a few monkey wrenches into the workings of the universe while he's there. Everyone has to have a hobby after all.

He refused to believe in reincarnation, but that was long ago, in another life, in a distinct universe. Sent in a world where the strong survives, and the weak perish, made his skin crawl. Luckily, he knows this world—he knows the board, and he knows the pieces.Time to make a move [Self Insert].